HP Serviceguard Extension for RAC (SGeRAC) manual Replacing a Lock Disk

NOTE: After executing one of the commands above, any I/O queued for the device will restart. If the device replaced in step #2 was a mirror copy, then it will begin the resynchronization process that may take a significant amount of time to complete. The progress of the resynchronization process can be observed using the vgdisplay(1M), lvdisplay(1M) or pvdisplay(1M) commands.

Offline Replacement of a Mechanism in an HA Enclosure Configured with Shared LVM (SLVM)

Hot plugging of disks is not supported for Oracle RAC data that is configured in volume groups with Shared LVM (SLVM). If you need this capability, you should use disk arrays for your Oracle RAC data.

If you are using software mirroring for shared concurrent activation of Oracle RAC data with MirrorDisk/UX and the mirrored disks are mounted in a high-availability disk enclosure, use the following steps to carry out offline replacement:

1.Make a note of the physical volume name of the failed mechanism (for example, /dev/dsk/ c2t3d0).

2.Deactivate the volume group on all nodes of the cluster:

#vgchange -a n vg_rac

3.Replace the bad disk mechanism with a good one.

4.From one node, initialize the volume group information on the good mechanism using vgcfgrestore(1M), specifying the name of the volume group and the name of the physical volume that is being replaced:

#vgcfgrestore /dev/vg_rac /dev/dsk/c2t3d0

5.Activate the volume group on one node in exclusive mode, then deactivate the volume group:

#vgchange -a e vg_rac

This will synchronize the stale logical volume mirrors. This step can be time-consuming, depending on hardware characteristics and the amount of data.

6.Deactivate the volume group:

#vgchange -a n vg_rac

7.Activate the volume group on all the nodes in shared mode using vgchange - a s:

#vgchange -a s vg_rac

Replacing a Lock Disk

Replacing a failed lock disk mechanism is the same as replacing a data disk. If you are using a dedicated lock disk (one with no user data on it), then you need to issue only one LVM command:

#vgcfgrestore /dev/vg_lock /dev/dsk/c2t1d0

After doing this, wait at least an hour, then review the syslog file for a message showing that the lock disk is healthy again.

Online Hardware Maintenance with Inline SCSI Terminator

Serviceguard allows online SCSI disk controller hardware repairs to all cluster nodes if you use HP’s inline terminator (C2980A) on nodes connected to the end of the shared FW/SCSI bus. The inline terminator cable is a 0.5 meter extension cable with the terminator on the male end that connects to the controller card for an external bus. The inline terminator is used instead of the termination pack that is attached to the controller card. The inline terminator makes it possible to physically disconnect the node from the end of the F/W SCSI bus without breaking the bus's termination. (Nodes attached to the middle of a bus using a Y cable also can be detached from

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